Understanding Why Spawn Traps Exist

The first thing I discovered about the Halo 4 spawning model was that
the Respawn Zone (RZ) was not the uber influencer like it was in Reach –
instead it was the Proximity Enemy Influencer (PE). CertainAffinity
told us that this was to ensure that we never spawn near an enemy. But
this changing of the influencer weights has fundamentally broke CTF and
Dominion, and enabled Spawn Traps in many maps, especially those that
use Respawn Zones.

CTF and Dominion Are Fundamentally Broken

When playing CTF, you may find yourself spawning on the wrong side of
the map, or even near the enemy flag. This, of course, breaks CTF at a
fundamental level, because you short cut two game elements and retard a
third – trek to the enemy base, overcome their defenses, and defend your
base.

For Dominion, you find yourself spawning across the map near the
enemy owned base rather than your own, and also potentially within the
base near your teammate. While the Dominion game is new, one cannot
argue that this was by design, since the Respawn Zone is obviously intended to anchor the spawning of players in or around their base, and the Anti Respawn Zone is obviously intended to discourage spawning within a base that is not owned by the spawning player’s team.

By their location on the map, as few as two or three players can
force their opponent to spawn on the wrong side of the map. When this
happens, if the spawning player has a teammate near the enemy flag or in
an enemy owned base, they can spawn near their teammate – and near the
enemy flag or in the enemy owned base.

There are actually several features that contribute to cross map spawning.

The PE Primary is too strong.[1] This has resulted
in pushing spawning players out of their team assigned Respawn Zones.
The PE Secondary, weak as it may be, can then push the spawning player
far across the map. 343 Industries recognized this problem and created a
fix for the Ricochet game type by making the Respawn Zone jump in
weight from +14 to roughly +200 when the Rico_Respawn label is attached
to it for the Ricochet game.

The PE Primary is too wide, making it possible for
only two or three on a team to cover their opponents’ Respawn Zones. It
would be ideal if 343 Industries patched the code to offer forgers a PE
Primary radii override setting within a trait zone. This would allow
forgers to adjust the radii for their maps’ sizes, geometries, and game
types (e.g., with or without Respawn Zones).

The Respawn Zones are too small. Instead of using
the Reach model of dividing the maps in half with two team assigned
Respawn Zones marked CTF, the zones are in some cases smaller than a
single PE Primary.

In the picture below, you will see one of the bases on Longbow with
three enemies covering the base’s Respawn Zone with their PE Primary
zones. The result is that every Respawn Point in the Respawn Zone is
driven down in weight to the point that the team that owns the base is
forced to spawn across the map.

But while the Respawn Zone can be overcome by PE Primaries to force
cross map spawning, it can also be manipulated to make Spawn Traps more
readily prosecuted.

Influencers’ Schedule of Weights Sustains Spawn Traps

The rescheduling of the Influencers’ weights is the reason that Spawn Traps are now sustainable in Halo 4.

If you take a look at Reach, the order of strength was RZ > Death
> PE. You see that a spawn trap was impossible to sustain, because
the Death Influencer was so strong that it would cause a player to spawn
away from where he died, even if that meant spawning behind the enemy
that killed him. In Reach, the Spawn Trap would literally collapse under
its own weight.

The above picture shows how the Death influencer at the Trap Point
lowers the weight significantly more than the Enemy Proximity can,
leaving the player to spawn behind one of the enemies.

(The values I used in the picture above are for illustrative
purposes, to get the point across that Death is far stronger than the
PE. We have no idea what the influencers’ values actually are.)

In Halo 4, the order of strength is PE > RZ > Death. This means
that not only is the spawning player trapped within the Respawn Zone,
but the spawning player cannot escape the Trap Point even if he dies
there – the Death Influencer cannot overcome either RZ or PE. In Halo
4, the Spawn Trap remains stable.

The above picture shows how the death influencer at the Trap Point
lowers the weight, but not nearly enough to break the Spawn Trap. It
also shows how the Respawn Zone limits the number of Respawn Points that
the red team must cover to force the Trap.

The publisher maps for the CTF playlist do not divide the map in half
with two Respawn Zones like the Reach maps did. As a result, some Halo 4
Spawn Traps are trivial.

In the picture above, the red team captures the blue team’s flag.
This leads to the CTF_RES_FLAG_AWAY assigned Respawn Zones on either
side of the base to activate.

The flag carrier takes a position to suppress one of the two blue
team Respawn Zones by himself. The other three red team members create a
cross fire Spawn Trap on the remaining blue team Respawn Zone. The red
team enjoy a position above the blue team spawns and out of their LOS
when they spawn.

The picture below shows an example of using Respawn Zones in Dominion
to create a Spawn Trap. You will see three members of one team create a
spawn trap behind a base on Longbow. Assuming that the spawning team
has only that base, they are bound to the base’s Respawn Zone and must
spawn somewhere in that Respawn Zone. (Respawn Points inside the base
are not shown in this picture.) Again, this is because the Respawn
Points within the Respawn Zone that are not covered by the enemy’s PE
Primary present the highest weighted Respawn Points on the map (well
over +5 in this case).

One last note about Spawn Traps, should you want to try this at home
yourself. The Line of Sight (LOS) Influencer is the most powerful
influencer on the typical map. If you are pointing your weapon at the
Trap Point, the spawning player will not spawn at the Trap under any
circumstances. The Trap works as long as you look away so that the Trap
Points are not in the field of view when you scope to the first scope
level (but you can see them along the edge of your field of view when
not scoped).

Small Has Its Limits

Drawing from the above conversation, let’s discuss forging small maps on the forge canvases.

Consider Shutout (presented by permission), a 4v4 map that put into
the matchmaking playlist. The PE Primaries of one team appear to be
capable of covering nearly every Respawn Point on the map. By carefully
positioning each player, the two Respawn Points on the bridge elbow are
purposely left uncovered, thus forming a Spawn Trap.

This map is familiar to forgers because it is a common community map
within the playlist and also a popular remake. For these reasons I felt
it was the best vehicle to demonstrate the severity of the problem at
hand. In essence, the PE Primary radii are freaking way out of
proportion for normal maps, and even worse for small maps.

Compare the PE Primaries’ radii of 9.5U in the picture above to
Adrift’s PE Primary radius of 5.5U, or Haven’s 7.0U radius, and you
begin to realize that the forge canvases[2] were intentionally
configured by 343 Industries for forging large maps, not small maps.

Summary

The schedule of weights has fundamentally broken CTF and Dominion by enabling cross map spawning.

The schedule of weight has enabled the sustaining of Spawn Traps, especially when Respawn Zones are used.

Just like Respawn Zones make Spawn Traps easier by reducing the area
an enemy needs to cover with their PE Primaries, small maps also make
Spawn Traps easy for the same reason.